Electrical connection



Oct. 16, 1934-. c G, BONDESQN 1 9724-26 ELECTRICAL CONNECTION Filed March 15, 1931 Patented (lot. 16, 1934 remit ELECTRICAL CONNECTION Carl G. Bondeson, Terryville, Conn., assignor to National Engineering Corporation, Conn, a corporation of Connecticut Terryville,

Application March 13, 1931, Serial No. 522,302

1 Claim.

' This invention relates to electrical connections, and more particularly, to a connection for grounding a conduit and a conductor in an electrical system to a water or other grounding pipe,

and in some of its specific aspects it is an improvement on the connection described and claimed in a patent to William E. Ecc1es,'Serial No. 1,914,010, issued June 13, 1933.

In such connections as heretofore provided, a

body portion of metal has means for receiving and attaching it to a water or other grounding pipe and to a conduit in the electrical system to be grounded, and usually means is provided on the body to receive a lug attached to a grounding wire carried by said conduit. l

' A feature of this invention is the provision of a grounding connection in which the lug provided for receiving the grounding wire is made so strong and sturdy that even though it be, as it is in the form of the invention herein illustrated, exposed and'liable to be struck by foreign objects when installed, it will effectually resist the blows which it may be expected to receive. By this provision it is unnecessary to sink the lug in a channel for protection, and hence it may be mounted in a position where it is easily accessible and conveniently soldered to the ground wire.

Another feature of this invention is the provision of means on the fixture which supports the lug for holding the latter against turning movement about the axis of the single screw by means of which it is fastened when the screw is being turned to tighten it in place so that the latter operation may be performed by one hand while the other is used for some other purpose.

A'further feature is the provision of means whereby the ground wire may be soldered to a terminal which is secured in place by the attach- 'ing screw, or alternatively the wire may be securely' clamped to the fixture by the action of the attaching screw. This is accomplished by providing on the surface of the fixture on which the lug lies a'wire groove leading from the point where the" conduit containing the wire is secured to the fixture and continuing around the securing screw spaced therefrom but within the area coveredby the lug. Hence, when a so-lderless "connection is satisfactory or permissible, after the grounding wire is merely laid in the groove, the lug is placed over it and then the screw is placed in position and tightened down. This will draw the lug firmly into contact with the ground wire (the groove being shallow enough so that part of the surface of the wire extends beyond the adjacent surface of the fixture) and hold the wire a grounding pipe, a conduit of the electrical sysstrengthening purposes webs or fillets 29 may be by having the part, which clamps the wire also arranged to 'have the wire soldered thereto, the

one and the same device may be used in:its entirety for either a soldered or. solderless job.

Other features and advantages will hereinafter appear.

In the accompanying drawing which shows one form of the invention; that at present preferred- Figure 1 is a side elevation of the ground connection with portions thereof omitted.

Fig. 2 isa plan view ofa: fixture of the connection.

Fig. 3 is a plan view of the ground connection of this invention showing the same attached to term, and the grounding wire soldered in the. lug as which is attached in place.

Fig. 4- is a longitudinal sectional View of the parts of the connector shown in Fig. 1.

Fig. 5 'is-a side View of the connection showing one of the fixtures in section with the grounding wire secured in place underthe lug.

Fig. 6 is a longitudinal sectional view of the lug to which the wire may be soldered or under which it may be secured.

In the embodiment of the invention shown in the accompanying drawing, the connection comprises two fixtures, a fixture 10 adapted to be connected to a conduit 11 and a fixture 12 adapted to be connected to a ground pipe 13 shown in Figs. 3 and 5. The fixture 12 is substantially the same as the corresponding fixture illustrated in the patent to William E. Eccles, Serial No. 1,914,010,

issued June 13, 1933, and comprises two jaw portions 14 and 15 provided with clamping surfaces adapted-to securely engage the grounding pipe and form good electrical and mechanical connection therewith. The two jaws 14 and 15 are structurally separate and have ears 18 engaged by clamp screws 19 passing through holes in the cars 18 in the clamping member 14 and into threaded bosses on the clamping member 15.

The fixture 10 which is adapted to be connected to the conduitll has a fiat portion or table 23 and a cylindrical portion 24, the latter being provided with integral screw threads-26 to receive external screw threads 28 on the conduit .11. The table 23 of the fixture is preferably formed integral "with the cylindrical portion 24 and for fixture 12 and a cylindrical socket 31 on the'fiat portion or table 23 of the fixturelO. The boss 30 and socket 31 have a comparatively loose fit and are provided for conveniently locating the parts one relative to the other for relative rotary movement preparatory to the securing of the parts together. When the fixtures are located in the desired angular positions relative to eachother with the cylindrical boss 30 in the socket 3l,-a,

screw 32 is passed through a hole 33 in the table portion 23 of the fixture 10 and enters a threaded hole 34 in the boss 30. Tightening of the screw causes the engaging surface at the base of the boss and the marginal edge of the cylindrical socket to be clamped in intimate contact with each other to thereby prevent rotation of the fixture 10 about i the fixture 12.

In this way the conduit pipe 11 is held in firm and good electrical and mechanical contact and connection with the grounding pipe 13.

In grounding electrical systems, it is desired also to not only ground the conduit 11 but also a grounding wire 35 which is carried by theconduit 11.

Heretofore, two methods of securing the end of the ground wire 35 were practiced. In one method the wire was merely wrapped around an attaching screw and such connectors are generally denoted by the term .solderless. In other cases the end of the wire was soldered to a tubular lug and the lug secured under an attaching :SCI'BW. According to the present invention, the device is so arranged that it may optionally be used in either way and with great facility, and hence it is unnecessary for the electrician or jobber to carry two different kinds of ground convneotions-one for solderless and the other for soldered jobsefiecting a saving and decreasing the capital outlay necessary to carry a proper stock of fittings, besides avoiding the delay and trouble necessary to pick out or obtain the proper fitting for the desired kind of work.

Further, with the lugs heretofore provided it has been found necessary in many instances to provide on the fixture which holds it adequate .--protection for the lug against blows or other damaging effects from foreign bodies. This has been accomplished by providing a channel in the fixture extending substantially around the lug, and 5 while thismethod'of protection has been adequate .the channel walls have impeded-free and convenient handling of the wire end and lug in soldering the former in the latter, and in fastening or unfastening the soldered lug.

i Accordingly, it is an object of the present-inventionto provide a lug which is of itself surficiently strong and rigid to require no protection, that is' to say, a self-protecting lug, and further to so arrange the lug and the fixture that either a soldered or solderless job may be performed with "i equal facility and'with. the same device. -Hence,

- thelug3'l'illustrated herein and shown in section in Fig; 6, is made preferably by casting it of a J Solid piece of metal of substantial thickness and size. It has a fiat bottom surface 38 and at one end is provided with a hole 39 for receiving the end of the wire 35 and the solder by means of which the wire 35 is electrically and mechanically united to the lug. The other end of the lug is decreased in thickness so as to constitute a flat portion 40 and has a hole 41 through which the attaching screw 32 may pass when being put in place and when, as shown in Fig. 4, the lug is assembled on the fixture 10 the head 32a of the screw engages the flat portion 40 of the lug and firmly holds the lug against the table 23 of the fixture l0.

Heretofore the lugs provided for attaching wires had just sufficient length to provide a portion for engagement with an attaching screw and a socket to receive the wire to be soldered in place. However, in order to protect the ground wire 35 from any damaging blows, the connector lug 3'? of the present invention is provided with an extension 41, see Fig. 6, having at least side walls 42 reaching beyond the socket 39 approximately to the end 43 of; the threaded cylindrical portion 24 of the fixture. Hence, as shown in Figs. 1, 3 and 4, the wire 35 is protected for its entirelength by the conduit 11, cylindrical portion 24, andlug 37.

Of course, it iswithin the scope of this invention to have the top wall 44 of the lug carried into the extension 41. However, in its preferred form,

this is not donefirst, because the walls 42 of the lug are adequate to protect the ground wire against blows in all directions, and, secondly, because the opening 45 thus formed permits the lugto be bent as indicated in dot-and-dashlines in Fig. 6, at an angle with respect to the general direction of the wire when soldering the lug to the wire, the. wire beingbent back into the spaces between the walls 42 after the soldering has been completed.

In order that the device may be used in performing a solderless job without the use of any additional parts and yet have the wire fully protected and securely clamped in goodelectrical and mechanical connection with the connector, the fixture 10 is provided with a wire groove 46 in the surface of the table 23 beginning at the junction of the table 23 with the cylindrical portion 24 and terminating in an annular groove 47 concentric with the hole 33 through which the attaching screw 32 passes. In using the device, the ground wire 35 is bared and led in the groove 46 and has its end loopedso asto fit in the annular groove 47. Then the lug 3'7 is placed over the wire and the attaching screw 32 is inserted through the holes 41 and 33 in the lug and fixture 10. respectively, and, engaging the threaded hole 34 in the fixture 11, is tightened in place. When this is done, the head 32 of the screw engaging the flat portion 40 of the lugdraws the lug tightly down against the ground wire, for the groove 46 and its annular portion 47 are formed in the surface of the table 23 in the area covered by the lug 37. Preferably the groove 46 and its annular portion 47 is made shallow so that the wire 35, shown in Fig. 5, extends above the surface of the table 23 and hence when the screw 32 is tightened the wire is firmly squeezed between the lug 3'7 and the 'table portion 23 of the fixture .10. The lug being rigid and strong firmly engages the bared end 350.

throughout its entire length and overlying the;

latter protects it from external blows.-

In order to facilitate the application of the lug 37 to the fixture 10, the portion 23 ofthe latter may and preferably is provided with upstanding ,nibs 48 between which the enlarged portion of the lug 47 extends when in proper position. These nibs 48 prevent the lug 37 from turning while the screw 32 is being tightened, thereby permitting the use of one hand of the mechanic for other purposes than for holding the lug while the other is applying the wrench screw-driver to the head 32a of the screw.

The annular portion 47 of the groove 46 in the table 23 may circumscribe the hole 33 in the fixture 10, but it is preferable that it be spaced therefrom by an annular wall 49, see Fig. 2, so as to avoid any possible damage being done to the wire or the loop portion of the wire being unwound as the result of the engagement with the shank of the screw.

Variations and modifications may be made within the scope of this invention and portions of the improvements may be used without others.

Having thus described the invention, what is claimed as new and for which it is desired to obtain Letters Patent, is:-

A grounding connection comprising a body having means for attachment to a conduit pipe containing a grounding wire, and means for attachment to a grounding pipe; and a lug removably mounted on said body and having a socket in which the end of the grounding wire may be inserted to be soldered to the lug, said lug having a surface throughout its length conforming substantially to the portion of the surface of the body underlying it to cover and clamp between itself and the body the end of the grounding wire to make a solderless electrical connection.

CARL G. BONDESON. 

